Commutator-brush and holder



(No Model.)` O. P. LOMIS.

GGMMUTATOR BRUSH AND HGLDEB. No. 407,225. Patented'July 16, 1889.

UNITED STATES.

PATENT CEEICE.

OSBCRN I. LOOHIS, CF SOMERVILLE, MASSACHUSETTS, ASSIGNOR TCl THE LOOMIS ELECTRIC MANUFACTURING COMPANY, OF NEV YORK.l

COMMUTATOR-BRUSH AND HOLDER.

SPECIFICATION forming part of Letters Patent No. 407,225, dated July 16., 1889. Application tiled February 23, 1889. Serial No. 300,898. (No model.)

To @ZZ whom, t may concern:

Be it known that I, OSBORN P. LOOMIS, a citizen of the United States, residing at Somerville, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Commutator- Brushes and Holders Therefor, of which the following is such a full, clear, and exact description as will enable any one skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings.

My invention relates to commutator appliances for dynamo-electric machines, and is equally applicable to such machines whether generators or motors.

The principal objects of the invention are to so improve the commutator-brush, the brush-holder, and its mountings and immediate connections that the strips or laminze of the brush may possess greater elasticity and yet be stout enoughto resist bending or buckling up; that theV brush may bear upon the commutator-eylinder with a yielding springpressure, so as to be held in close engagement therewith; that the machine may be reversed without necessitating readj ustment of the brushes, and that good electric connection or circuit between the cominutator and the terminals may be obtained. y

To these purposes the invention consists in the certain novel and peculiar constructions and arrangements of the brush, the brushholder, and its mountings and connections, all as hereinafter fully described, and then pointed out in the claims.

In the accompanying drawings illustrating my invention, and in which like numbers of reference designate like and corresponding parts throughout, Figure l is a reduced View of my improved apparatus, taken in section on line l 1, Fig. 2. Fig. 2 is a plan view of y the apparatus with part of the armature shown. Fig. 8 is a detached detailed view, partly in section.

Referring to the drawings, the number 5 designates the armature, G the armatureshaft, and 7 the coinmutator-cyli'nder mounted on and turning with the said shaft and having the usual radial commutator-segments. Upon the shaft G, and toward the outer end thereof, is the brush-liolder yoke S, provided.- with the insulated handle 9, and so mounted on the armature shaft as to be rotatable thereon in a vertical plane, in the usual way, in order to shift the position of the brushes relative to the commutator.

At or near each end of the yoke S is secured a metallic terminal-plate l0, which is fastened in position by means of screws l1 ll, set in the yoke, and theplate is completely insulated from the yoke by suitable insulating material 1-2-vulcanite, for instance. The plate has a binding-post 1.23, which serves as aterminal for the machine. The plate is provided with two perforated hinge-ears 14 14, preferably cast therewith, and into the perforations of which take the pintles l5 l5 of the swinging brush-holder l0, which is arranged so as to swing in a plane parallel with or containing the axis of the commutator cylinder or shaft, and it is movable in toward or out from the commutator in a manner that is evident from the drawings.

To the inner face of the brush-l'iolder is attached by suitable screws 17 the back or bed plate 1S of the commutator-brush, which is composed of flat strips 19 lf), made of suitable metal. These strips or laminzc are preferably soldered to the bed-plate 1S, though they may be attached thereto in any other suitable way.

The shape of the brush-laminze l0 is peculiar and constitutes part of my invention. ln shape the leaves or laminze 19 are flat, with a broad base 20, from where they taper to their free contact ends 2l, which are formed on arcs about of a curvature equal that of the commutator, with which they are held in sliding contact. The contact ends are also beveled off, as clearly indicated in Fig. 2, so that the contact-making surfaces thereof are considerably increased. By virtue of this peculiar shape the laminze are rendered very pliant. At the same time they are sufliciently rigid and stout near their attaching ends or bases to resist any stress that would tend to make them bend or buckle up transversely.

The brush-lamime bear obliquely end-on upon the com mutator, and are each disposed in a plane that is oblique to the axis of the eommutator 7 and normal to the plane et the commutator-segment passing thereunder.

Electrical connection between the term i nalplate IO and the brush-holder lG is made by means of the hinge ears and pintles, and also by means oli' the contact-spring secured to the plate by screws 23 and bearing upon the rounded end 2lot' the brush-holder. 'lhis contact-spring is split at its free end into iingers in order to insure more perfect contact. The brush-holder 16, and thus the brush earried thereby, is forced in toward the commutator 7, under yielding spriiig-pressure, by the coilspring 25, connected by one end to the holder and by the other end to the bruslr `holder yoke 8, which, considered in reference to the plane in which the holder swings, is iixed. The tendency ol spring is to normally hold the brush-holder in toward the connnutator, and this causes the brush to bear thereon with a yielding pressure, in addition. to the spring-pressure imparted bythe brushlaminze themselves.

To have a circuit lead over a hinge-joint or sliding contacts is objectionable it'or several obvious reasons. In the case of a hingej oint the same necessarily has to belubricated, and the caking el' the lubricant lis a great disadvantage. In my improved apparatus I am enabled to easily avoid this by placing the terminal 13 directly upon the bruslrholder il (i, as indicated in broken lines in Fig. 2. It preferred, the pintle l5 oit the holder may be e.\' tended and fashioned into asuitablebindingpost. In both of these latter constructions making circuit over sliding contacting-surfaces is obviously avoided.

The several parts of the described apparatus are to be made ol suitable metals where electrical conduction is required. The parts are duplicated upon diametrically-opposite sides ol the commutator and the yoke in a way that will be readily understood from the drawings.

From the oblique arrangement of the brushlamime and the pressure of the lnush-holder in toward the eommutator the laminae are always maintained in close broadsidc contact with each other and kept well hunched. Should a strip lil become hooked in a comnnitator-segment it would be easily stripped from the brush without likely damage to the adjacent lamina.

The improved alil'iaratus nfovides a very flexible brush, giving good electrical connections, and one that does not require shiftingl upon reversal of the machine. y

I do not confine myself to the exact constructions and arrangements herein shown, .for obviously there may be various modilications made in the same without, however, making a substantialdeparture from the spirit of the invention.

yoke. 'lhese sockets are indirated in solid black. Il preli'er1.' ed,a hard-rubber hook can be used.

Ilaving thus described my improvements, what I claim as my invention, and desire to secure by Letters Patent, is-- l. In a dynamo-electric machine, the com` bination, with the commutator-cylinder, ol a terminal-plate mounted on a support and insulated therefrom, and a brush-holder having a brush andhingei'l to said plate, Vfor the purpose set forth.

In a dynamo-electrie machine, the oombination, with the commutator-cylinder, ol' the lnfush-l1older yoke and a terminail-plate mounted thereon and insulated therefrom, a brush-holder carrying a brush and hinged to said plate, and a spring `for :forcing the holder in toward the comm utator to hold the brush in engagement therewith, substzlntially as and for the purpose set forth.

In a dynamoeleetrie machine, the vombination, with t-he commutator-eylinder, ot a brush composed ol' the strips or lamina. lll lh, broadened at their attaching ends 2h and tapering toward their contact ends 2 l, whereby the laminse may be pliant, at the same time stout enough to resist lmcklingl up, substantially as set forth.

et. In a dynamo-electrie machine, the eombination, with the commutator-cylinder 7, of; the brush-holder yoke S, the terminal-plate ilo, mounted thereon and insulated therefrom, the swinging brush-holde r il l, ea rigy'ii'lg a brush and hinged to the said plate in electrieai connection therewith, the spring 22, mounted on the said plate l() and mg-aging the said brush-holder 1G, the termim'd-post l, and a spring :for forcing the holdinl in toward the said connnul'ator, substantiall y as and for the purpose set forth.

In a dynamo-eleetrie machine, the com bination, with the conimutatl'ir-cylinder 7, of the lnfuslrholder yoke S, the terminalfplz'tte lO, mounted on and linsulated .from the yoke, the swinging brilsh-holder il f3, carrying abrush and hinged to said plate l0, in electrical con neetion therewith, the spring 22, mounted on the plate .l0 and engaging the luh'ler 16, the terminal-post Vlli and lthe spring 2*, intermediate the holder lo, and yoke s, l'or forcing the holder in toward the commutator, substantially as and for the purpose set forth.

l1. In a dynamo-electricmachine, the eembination, with a swinging brush-ladder, eonsisting in. a bar, such as a bar ill, ol' a bedplate, such as a bed-plate lis, see/uml to the bar and having the lnush-hnninae attaefhml thereto, .for the purpose d escrilnul.

7. In a dynamo-cleet1ic machine, the eo|nbination, with a terminal-plate 10, suitably and aiiixed my seal, this 20th day' of -Febmounted and insulated and provided With ruary,1889,in thepresenoe of two subscribing Io perforated hinge-ears 14, of a brush-holder, Witnesses. such as 16, Carrying a brush, and having T 5 llinge-pintles l5, for hiuging with the ears OSLORB P` LOOMIS' [L' Si 14, substantially as and for the purpose set Vitnesses: forth. PAUL F. C. TUCKER,

In testimony whereof I have set my hand VILLIS FOWLER. 

